1. Field of the Invention
The present invention results to a recording apparatus and method and a recording medium for recording the projecting method which are suitable to a projector, etc.
2. Description of the Related Art
In some projectors for a liquid crystal system using a transmission type color LC panel as well as DLP (Digital Light Process-registered trademark) system using a reflection type spatial light modulator called a micro-mirror element, a correct rectangular aspect-ratio (for example, a vertical 3: a horizontal 4) image is actually projected in a deformed state, that is, in a state enlarged in a direction away from a project, due to an optical axis of a projecting lens system not set perpendicular to a screen plane as a projection target.
In order to correct such a deformed rectangular projected image, an image sensor, phase difference sensor, etc., are provided in the projector and a relative positional relation is obtained so as to grasp the generation state of the deformation. By doing so, a light image of a corresponding reverse-direction deformation is formed on a light image forming element, such as a color, LC panel, micro-mirror element, etc., to allow an image deformation to be cancelled on the image screen. This trapezoid correction technique has been adopted on an associated product or products.
Another projector is also known which is set opposite to a screen and it includes a monitor camera located at the front surface of the projector body to allow a focusing adjustment, a zooming adjustment to the screen frame, a trapezoid adjustment, etc., to be automatically done, a CPU configured to process the information of a video signal input from the monitor and calculate a focusing adjustment value, zooming adjustment value and a trapezoidal deformation adjustment value, a display drive section configured to adjust a projection lens for focusing, zooming and trapezoid deformation adjustment, and an input image data conversion section configured to convert an input image to display data and output a converted one to the display drive section (for example, Patent Document 1-JPN PAT APPLN KOKAI NO. 2000-241874).
The above-mentioned trapezoid correction technique is based on the concept of obtaining a projected image or an image projected screen state by an image sensor and phase difference sensor. Since, however, the image sensor, or a phase difference sensor, and an image projecting lens cannot naturally be arranged on the same axis and are arranged in front of the projecting apparatus in a state away therefrom.
However, a “parallax” problem arises according to a spaced-apart distance, thus lowering an accuracy with which trapezoid correction is made.
In addition, the trapezoid correction technique comprises partially compressing on otherwise deformed rectangular form and, by doing so, projecting an exact aspect-ratio rectangular form, so that, the greater the extent of deformation, the smaller the rectangular form to be projected after the correction is made.